BANGKOK, Jan. 23 (Xinhua) -- Thailand's livestock authorities on Tuesday confirmed the country's second case of bird flu outbreak this year, saying they had detected the deadly H5N1 virus among chickens in the northeastern border province of Nong Khai.

    The results of laboratory tests confirmed H5N1 virus in some 200 chickens at a poultry farm in Nong Khai, a senior livestock department official was quoted by Thai News Agency as saying.

    Earlier reports said that some 2,000 chickens at the farm had been culled, in Si Chiangmai district, Nong Khai province, some 615 km northeast of Bangkok, bordering Laos, after the 230 chickens at the farm died of unknown causes last Saturday.

    Thailand's Livestock Development Department director-general Pirom Srichan said the district has been declared an outbreak area with round-the-clock monitoring to prevent the illegal movement of poultry.

    The first bird flu outbreak of this year was reported on January 15 when authorities confirmed that the H5N1 virus was found in dead ducks in northern province of Phitsanulok.